summaryrefslogtreecommitdiff
path: root/external/aspnetwebstack/src/System.Web.Helpers/DynamicJsonObject.cs
blob: d30842cdbd95e529b22b6e68da84f6b7efab521c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
// Copyright (c) Microsoft Corporation. All rights reserved. See License.txt in the project root for license information.

using System.Collections.Generic;
using System.Diagnostics;
using System.Dynamic;
using System.Globalization;
using System.Linq;
using System.Web.Helpers.Resources;

namespace System.Web.Helpers
{
    // REVIEW: Consider implementing ICustomTypeDescriptor and IDictionary<string, object>
    public class DynamicJsonObject : DynamicObject
    {
        private readonly IDictionary<string, object> _values;

        public DynamicJsonObject(IDictionary<string, object> values)
        {
            Debug.Assert(values != null);
            _values = values.ToDictionary(p => p.Key, p => Json.WrapObject(p.Value),
                                          StringComparer.OrdinalIgnoreCase);
        }

        public override bool TryConvert(ConvertBinder binder, out object result)
        {
            result = null;
            if (binder.Type.IsAssignableFrom(_values.GetType()))
            {
                result = _values;
            }
            else
            {
                throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, HelpersResources.Json_UnableToConvertType, binder.Type));
            }
            return true;
        }

        public override bool TryGetMember(GetMemberBinder binder, out object result)
        {
            result = GetValue(binder.Name);
            return true;
        }

        public override bool TrySetMember(SetMemberBinder binder, object value)
        {
            _values[binder.Name] = Json.WrapObject(value);
            return true;
        }

        public override bool TrySetIndex(SetIndexBinder binder, object[] indexes, object value)
        {
            string key = GetKey(indexes);
            if (!String.IsNullOrEmpty(key))
            {
                _values[key] = Json.WrapObject(value);
            }
            return true;
        }

        public override bool TryGetIndex(GetIndexBinder binder, object[] indexes, out object result)
        {
            string key = GetKey(indexes);
            result = null;
            if (!String.IsNullOrEmpty(key))
            {
                result = GetValue(key);
            }
            return true;
        }

        private static string GetKey(object[] indexes)
        {
            if (indexes.Length == 1)
            {
                return (string)indexes[0];
            }
            // REVIEW: Should this throw?
            return null;
        }

        public override IEnumerable<string> GetDynamicMemberNames()
        {
            return _values.Keys;
        }

        private object GetValue(string name)
        {
            object result;
            if (_values.TryGetValue(name, out result))
            {
                return result;
            }
            return null;
        }
    }
}